diff options
Diffstat (limited to 'arch/sh64/lib/memcpy.c')
-rw-r--r-- | arch/sh64/lib/memcpy.c | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/arch/sh64/lib/memcpy.c b/arch/sh64/lib/memcpy.c new file mode 100644 index 000000000000..c785d0aa194d --- /dev/null +++ b/arch/sh64/lib/memcpy.c | |||
@@ -0,0 +1,82 @@ | |||
1 | /* | ||
2 | * Copyright (C) 2002 Mark Debbage (Mark.Debbage@superh.com) | ||
3 | * | ||
4 | * May be copied or modified under the terms of the GNU General Public | ||
5 | * License. See linux/COPYING for more information. | ||
6 | * | ||
7 | */ | ||
8 | |||
9 | #include <linux/config.h> | ||
10 | #include <linux/types.h> | ||
11 | #include <asm/string.h> | ||
12 | |||
13 | // This is a simplistic optimization of memcpy to increase the | ||
14 | // granularity of access beyond one byte using aligned | ||
15 | // loads and stores. This is not an optimal implementation | ||
16 | // for SH-5 (especially with regard to prefetching and the cache), | ||
17 | // and a better version should be provided later ... | ||
18 | |||
19 | void *memcpy(void *dest, const void *src, size_t count) | ||
20 | { | ||
21 | char *d = (char *) dest, *s = (char *) src; | ||
22 | |||
23 | if (count >= 32) { | ||
24 | int i = 8 - (((unsigned long) d) & 0x7); | ||
25 | |||
26 | if (i != 8) | ||
27 | while (i-- && count--) { | ||
28 | *d++ = *s++; | ||
29 | } | ||
30 | |||
31 | if (((((unsigned long) d) & 0x7) == 0) && | ||
32 | ((((unsigned long) s) & 0x7) == 0)) { | ||
33 | while (count >= 32) { | ||
34 | unsigned long long t1, t2, t3, t4; | ||
35 | t1 = *(unsigned long long *) (s); | ||
36 | t2 = *(unsigned long long *) (s + 8); | ||
37 | t3 = *(unsigned long long *) (s + 16); | ||
38 | t4 = *(unsigned long long *) (s + 24); | ||
39 | *(unsigned long long *) (d) = t1; | ||
40 | *(unsigned long long *) (d + 8) = t2; | ||
41 | *(unsigned long long *) (d + 16) = t3; | ||
42 | *(unsigned long long *) (d + 24) = t4; | ||
43 | d += 32; | ||
44 | s += 32; | ||
45 | count -= 32; | ||
46 | } | ||
47 | while (count >= 8) { | ||
48 | *(unsigned long long *) d = | ||
49 | *(unsigned long long *) s; | ||
50 | d += 8; | ||
51 | s += 8; | ||
52 | count -= 8; | ||
53 | } | ||
54 | } | ||
55 | |||
56 | if (((((unsigned long) d) & 0x3) == 0) && | ||
57 | ((((unsigned long) s) & 0x3) == 0)) { | ||
58 | while (count >= 4) { | ||
59 | *(unsigned long *) d = *(unsigned long *) s; | ||
60 | d += 4; | ||
61 | s += 4; | ||
62 | count -= 4; | ||
63 | } | ||
64 | } | ||
65 | |||
66 | if (((((unsigned long) d) & 0x1) == 0) && | ||
67 | ((((unsigned long) s) & 0x1) == 0)) { | ||
68 | while (count >= 2) { | ||
69 | *(unsigned short *) d = *(unsigned short *) s; | ||
70 | d += 2; | ||
71 | s += 2; | ||
72 | count -= 2; | ||
73 | } | ||
74 | } | ||
75 | } | ||
76 | |||
77 | while (count--) { | ||
78 | *d++ = *s++; | ||
79 | } | ||
80 | |||
81 | return d; | ||
82 | } | ||